Model railroad turntable



NOV. 10, 1959 MAHAN E 2,911,922

MODEL RAILROAD TURNTABLE 4 Sheets-Sheet 1 Filed June 10, 1957 WWWmvzmons A. MAHAN O. 0. LEE

PATENT AGENT Nov. 10, 1959 Filed June 10, 1957 FIG. IA

L. A. MAHAN ET AL MODEL RAILROAD TURNTABLE 4 Sheets-Sheet 2 INVENTORSLABAN ALBERT MAHAN Q) ORAN .OTIS LEE PATENT AGENT NOV. 10, 1959 H N ETAL2,911,922

MODEL RAILROAD TURNTABLE 4 Sheets-Sheet 3 Filed June 10, 1957 'INVENTORSLABAN ALBERT MAHAN ORAN OTIS LEE PATENT AGENT 4 Sheets-Sheet 4 I I s H RN H w E G M Mm II V WW8 T 0 8 vb 99 mu w 1. M n J A mm B L /M N M I In Mlalllil mm \W i A l/ Nov. 10, 1959 A. MAHAN ET AL MODEL RAILROADTURNTABLE Filed June 10, 1957 Q. i s; v Fo m mm BY K PATENT AGENT UniteStates Patent 911,922 MODEL RAILROAD TURNTABLE Laban Albert Mahan andOran Otis Lee, San Antonio, Tex.

Application June 10, 1957, Serial No. 664,816

3 Claims. (Cl. 10438) This invention relates to model railroadturntables, more particularly this invention relates to electric modelrailroad turntables which are precise in alignment and are controllableby electrical means.

The prior art illustrates a number of turntables for electric railwaysystems. Some of these are rather simple requiring manipulation by handin order to effect adjustment. Others, of course, have more complexarrangements adapted to be adjusted by electric motive means. Theelectrically operated turntables of the prior art are diflicult to alignprecisely unless complex means are provided for automatically aligningthe tracks of the turntable with the access tracks.

It is therefore an object of the invention to provide a model railroadturntable.

It is another object of the invention to provide a model railroadturntable which is electrically controlled for precise alignment withaccess tracks.

It is still another object of the invention to illustrate anelectrically controlled model railroad turntable in which positivedriving mechanism is provided.

It is yet another object of the invention to teach an electricallycontrolled railroad turntable in which a unique aligning means isprovided.

It is yet another object of the invention to provide a model railroadturntable which has a novel latching means for locking the turntable inalignment with access tracks.

With the foregoing and other objects in view, the invention will be morefully described hereinafter, and will be more particularly pointed outin the claims appended hereto.

In the drawings wherein like symbols refer to like or correspondingparts through the several views;

Figure 1 together with Figure 1A is a top plan view of the modelrailroad turntable.

Figure 2 is a fragmentary cross section of the turntable of thisinvention taken along lines 22 of Figure 1A.

Figure 3 is a fragmentary cross section of the turntable of thisinvention taken along lines 3-3 of Figures 1 and 1A.

Figure 4 is a fragmentary cross section of the turn table of thisinvention taken along lines 44 of Figure 2.

Figure 5 is a partially broken out left side elevation.

Figure 6 is a schematic view of the electrical circuitry necessary for apreferred mode of operation of the turntable.

Turning now to the drawings, particularly to Figures 1 and 1A, referencenumeral 10 refers to a stationary circular base. The circular base isprovided with an upwardly extending center post 11. A rotatable circularplatform 12 is coaxially mounted on the circular base 10 and employs theupwardly extending post 11 as its axis. A rectangular track supportingrotating platform 13 is also coaxially mounted on upwardly extendingpost 11 and above the rotating circular platform 12. Rotating platform13 has a Smaller radial dimension than base ice 10. The upper surface ofthe platform 13 is provided with longitudinal rails 14 and 15 to form atrack arrangement. It is pointed out that the rails extend beyond theplatform 13 at both ends.

The circular base 10, rotating circular base 12 and rectangular platform13 may be constructed of nonconducting material such as plywood. Therectangular platform 13 has side reinforcing metal strips 16 and 17which are secured by suitable means such as screws. The rectangularplatform 13 is supported on wheels 18, 19, 20, 21 which roll on registerrails 22 and 23. The register rails 22 and 23 are mounted along theperiphery of base 10. Each rail describes one half of the circumferenceand are not joined. Figures 1 and 1A show painted guide lines 24 and 25on the circular platform 12 adjacent the edges of rectangular platform13 and parallel thereto. More will be said in connection with guidelines 24 and 25.

The rotating circular platform 12 has a metal strip 26 secured aroundthe edge to which a rack 27 is aflixed. A turntable drive motor 28powered by leads 69 and 70 is mounted on one end of strip metal base 29which is hingedly fastened to the base 10 by a pivot means 30 which maybe a screw. The drive motor actuates worm gear 31 mounted longitudinallythe base 29 through flexible coupling 32 and is positioned to be inoperative relationship with rack 27. The worm gear 31 is suitablyjournalled by hearing means 33. The said metal strip base 29 is biasedby spring means 34 to keep the worm 31 in operational mesh with the rack27. A slot 35 near the upper end of base 29 and screw 36 provide, incooperation with pivot means 30, limited free movement of base 29 andworm 31 in order to accommodate minor irregularities in the rack 27.

A conductor clip 37 is fastened by a screw 38 to the stationary base 10and is disposed to be in slidable engagement with the metal strip 26.Lead 39 provides current to the clip.

It is seen that Figure 3 illustrates the pivoting arrangement betweenthe stationary base 10, the circular platform 12 and the tracksupporting platform 13. Reference numeral 40 designates a slightlycupped metal washer which serves as a friction free thrust washer tosupport the rotating circular platform 12. The center portion ofplatform 12 is fitted with tubular bushing 41 through which passes thecenter post 11, and around which the cap bushing 42 floats which isfitted into the center of the rectangular track supporting rotatingplatform 13. The top of the cap bushing 42 has a thrust plate 43 mountedthereon which engages the upper end of the center post 11. It will beappreciated that the assembly provides essentially friction free supportfor the turntable 13. It is also seen that electrical contact betweenthe center post 11 and the thrust plate 43 is always maintained. In linetherewith, it is seen in Figure 3 that a lead wire 44 runs along theunder side of circular base 10 and is secured by suitable means to thecenter post 11. In Figure 1A, a lead wire 45 is illustrated whichconnects the thrust plate 43 with one of the rails 14. Additionally,conductor 44A and flexible conductor 45A provide current from metalstrip 26 to rail 15. More will be said later about the function of theseconnections.

Now turning to the locking mechanism of the turntable, which is securedat both ends of the rectangular platform 13. Figures 1 and 1A illustratethe mechanism in a locked position to afford alignment with accesstracks. Figure 1A clearly illustrates the unique mechanism since aportion of the rectangular platform 13 is broken away. The actualsecuring element is designated by reference numeral 46 which is in theform of a tongue and adapted to fit into any one of a series of detents46A.

In connection therewith note Figure 4. The detents are punched ordrilled in the register rails 22 and 23. In order to more fullyunderstand the structure of the locking mechanism reference is made toFigure 2 as well as the above-mentioned Figure 1A. The securing elementis a locking slide 46 which is spring loaded by means of spring 47. Oneend of the spring is fastened to the projection 48 of the support plate49. Another support plate 50 is provided to complete the retaining meansfor the locking slide 46. Guide plates 51 and 52 keep the looking slidein parallel disposition with the long axis of the platform 13. The guidemechanism is illustrated by dotted lines in Figure 1A. Both Figures 1Aand 2 show a flexible wire jumper 53 which communicates with the tongueportion of the slide 46 and the rail contactor blade 54 which isconnected to rail 15. Another contactor lade 55 is provided for rail 14.The contactors 54 and 55 are made of metal which project beyond therails 14 and 15 in a manner to make contact with the access tracks.Jumper connector 53A connects rail 14- with contactor blade 55. Thelocking mechanism is loosely fitted by means of a hole over upwardlyextending projection pin 56 which is secured to one end of linking strip57. Link 57 is pivotally mounted at its other end to rotating circularplatform 12.

In order to understand the electric energizing means for this inventionthe following disclosure will entertain a detailed description thereofwith particular reference to Figure 6. To provide power for actuation ofthe motor 28 and for energizing the track rails power leads 68 and 61may be connected to any suitable source of direct current. Reversingswitches 62 and 63 are situated between'the motor and the connectionsfor energizing the tracks, respectively. A selector switch 6 isconnected to one of the poles of reversing switch 63 so that it receivescurrent only when the switch is in either operative position and not theoff position. Selector switch 64 conducts current through leads 64A and6413 to either one or the other of register rails 22 and 23. It will bereadily appreciated that depending on the position of the reversingswitch 63 the rails 14 and 15 may be positive or negative in order todrive the locomotive either forward or reverse. Also, it is seen thatdepending on the position of the reversing switch 62 the motor 28 willdrive the circular platform 13 either in clockwise fashion or in acounter clockwise direction. Selector switch 64, if in the oil?position, prevents the access tracks from becoming energized. If,however, it is desired to run a locomotive from the turntable trackonto, say rails 65 and 66 of Figure 6, and keep it in motion thereon,the selector switch 64 must be placed in position to supply current toregister rail 23 from whence rail 66 is energized by conducting currentthrough the locking mechanism 46, through the jumper wire 53 and thecontactor blade 54. To run the locomotive from the turntable to theother tracks made up of rails 67 and 68, in Figure 6, the selectorswitch 64 must be placed to energize register rail 22 from whence rail68 is energized by means of the oppositely disposed locking slide,jumper wire and coin tactor blade. it is seen that rail 14 is alwaysenergized by means of switch 63 and, therefore, the oppositely disposedrails 65 and 67 are energized without the use of switch 64 by thecontactor blades which are always electrically connected to rail 14 bymeans of jump wires. The rail contactor blades associated with rail 15are insulated therefrom and consequently are not electrically connectedthereto.

In the operation of the locking arrangement of this invention thefollowing discussion is provided. In order to set the turntable inmotion the switch 62 is thrown in one direction or the other which sendscurrent through leads 69 and 70 to the motor 28 to actuate the circularplatform 13 in either a clockwise or counter clockwise direction. As theplatform rotates the pivot means engaging one end of the link 57 moveswith it until it is at a small angle with the locking mechanism, atwhich time the projection pin 56, which is fastened to the other end ofthe link, strikes the edge of the hole in locking slide 46, into whichit fits loosely. Further rotation of the platform 12 begins to pull thelocking slide 46 against the spring 47 effecting withdrawal of thetongue of the slide from the detent 46A. Additional rotation of theplatform 12 drags the turntable 13 in the same direction. It will beappreciated that should the turntable '13 attempt to overtake theplatform 12 the tension of spring 47 will relax, thereby increasing thedrag friction between the register rails and the locking slide. As aresult, there is effected a drag having a constant angular velocity. Inthe event that some slight sticking takes place, the bumper pins 71 willengage the metal side strips 16 and 17 of the turntable platform 13which will nudge the platform beyond the sticky spot, and therefor actas safety pins for the mechanism.

When the locking slide reaches the next detent in the register rail, itwill snap into position. The operator upon seeing this closeapproximation to the new tracks reverses the drive motor 28 until guidelines 24 and 25, painted on platform 12, are parallel to the sides ofthe rectangular platform 13, as illustrated by Figures 1 and 1A. At theconclusion of the manuever the link 57 has again moved in axialalignment with the locking slide 46 so that the spring may exert maximumtension on the slide in a manner to thrust outwardly the locking slide.As a result of the operation the turntable rails 14 and 15 will be inprecise alignment with the new set of access rails.

It will be noted that while the tracks shown are of the two railvariety, it is entirely practicable to employ the three rail type. Insuch an event, the center rail and one outside rail will be employed asenergizing means for the locomotive.

Additionally, it will be noted that no attempt has been made to indicatethe number of positions to which the turntable may be turned. It is inthe purview of the invention to provide a small number of positions or alarge number since the actual number of positions available may be madeby choice.

Although we have disclosed herein the best form of the invention knownto us at this time, we reserve the right to all such modifications andchanges as may come within the scope of the following claims.

We claim:

1. A model railroad turntable comprising a horizontally disposed fiatbase having vertically extending pivot means located on the uppersurface substantially in its center, a first horizontally disposedplatform rotatably mounted on said pivot means, a second horizontallydisposed platform above the first platform rotatably mounted on saidpivot means, two parallel rails mounted on said second platform, atleast one latch means attached to said second platform, said latch meansincluding an elongated horizontal slide biased outwardly in a horizontalplane, the outwardly extending end of the slide being in slidingengagement with means on said base, a link means connecting the otherend of said slide with the first platform.

2. A model railroad turntable comprising a horizontally disposed flatbase having vertically extending pivot means located on the uppersurface substantially in its center, a first horizontally disposedplatform rotatably mounted on said pivot means, a second horizontallydisposed platform above the first platform rotatably mounted on saidpivot means, motive means for rotating said first platform about saidpivot means, two parallel rails mounted on said second platform, acircular register rail mounted on said flat base perpendicular to theupper surface having as its axis the said pivot means, said rotatablesecond platform being adapted to ride on said register rail, at leastone latch means attached to said second platform, said latch meansincluding an elongated horizontal slide biased outwardly in a horizontalplane, the outwardly extending end of the slide being in slidingengagement with the inner side of said register rail, the register railhaving a plurality of retaining means to receive the outwardly extendingend portion of said slide, a link means connecting the opposite end ofsaid slide with the first platform.

3. In a model railroad turntable associated with a plurality of accesstracks, comprising a horizontally disposed flat base having verticallyextending pivot means located on the upper surface substantially in itscenter, a first horizontally disposed circular platform rotatablymounted on said pivot means, a rack mounted along the edge of said firstplatform, a worm gear in operative relationship with said rack, saidworm gear being driven by electric motive means, a second horizontallydisposed rectangular platform above the first platform, the secondplatform mounted on said pivot means, at least two rails mountedlongitudinally on said platform, a first electric connector means forenergizing one of said rails, a second electric connector means forenergizing another of said rails, a

circular register rail mounted on said flat base perpendicular to theupper surface having as its axis the said pivot means, the register railbeing separated at two oppositely disposed points, said rotatablerectangular platform being adapted to ride on said register rail, atleast one latch means attached to said second platform, said latch meansincluding an elongated horizontal slide biased outwardly in a horizontalplane, the outwardly extending end of the slide being in slidingengagement with the inner side of said register rail, the register railhaving a plurality of retaining means to receive the outwardly extendingend portion of said slide, a link means connecting the opposite end ofsaid slide with the first platform.

References Cited in the file of this patent UNITED STATES PATENTS197,358 Gilbert et al. Nov. 20, 1877 1,087,424 Bauman Feb. 17, 19141,689,160 Siegrist Oct. 23, 1928 1,783,669 8 Becker NOV. 25, 19302,629,336 Seidel Feb. 24, 1953

